Strongyloides is a human parasitic nematode that is poorly understood outside a clinical context. This article identifies gaps within the literature, with particular emphasis on gaps that are hindering environmental control of Strongyloides. The prevalence and distribution of Strongyloides is unclear. An estimate of 100-370 million people infected worldwide has been proposed; however, inaccuracy of diagnosis, unreliability of prevalence mapping, and the fact that strongyloidiasis remains a neglected disease suggest that the higher figure of more than 300 million cases is likely to be a more accurate estimate. The complexity of Strongyloides life cycle means that laboratory cultures cannot be maintained outside of a host. This currently limits the range of laboratory-based research, which is vital to controlling Strongyloides through environmental alteration or treatment. Successful clinical treatment with antihelminthic drugs has meant that controlling Strongyloides through environmental control, rather than clinical intervention, has been largely overlooked. These control measures may encompass alteration of the soil environment through physical means, such as desiccation or removal of nutrients, or through chemical or biological agents. Repeated antihelminthic treatment of individuals with recurrent strongyloidiasis has not been observed to result in the selection of resistant strains; however, this has not been explicitly demonstrated, and relying on such assumptions in the longterm may prove to be shortsighted. It is ultimately naive to assume that continued administration of antihelminthics will be without any negative long-term effects. In Australia, strongyloidiasis primarily affects Indigenous communities, including communities from arid central Australia. This suggests that the range of Strongyloides extends beyond the reported tropical/subtropical boundary. Localized conditions that might result in this extended boundary include accumulation of moisture within housing because of malfunctioning health hardware inside and outside the house and the presence of dog fecal matter inside or outside housing areas.

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Resistance in barley to scald caused by Rhynchosporium commune is readily overcome as virulent pathotypes in the pathogen population are selectively favoured over less virulent pathotypes. Diverse sources of resistance amongst host accessions have been found upon screening a wide array of accessions from around the world. Deciding which of these is of greatest value, and which are different from each other, takes a much greater investment of time and effort. This paper reports on the use of seedling screening techniques using 262 individual scald isolates collected from around Australia, to identify the most useful resistance sources from amongst 30 previously selected. No resistance source was effective against all isolates, but some such as Pamunkey, CI8618, CI4364 and ICARDA 4 were shown to have resistance to most isolates, whilst others were much less useful. Some of the most effective donors were shown to likely have more than one gene involved. The value of gene pyramids is discussed, as are the advantages and pitfalls of transferring the resistances from poorly adapted genetic backgrounds into better-adapted breeding lines so that they can more readily be used by breeding programs. This is a work in progress and the introgressed resistances being developed are available to all.